Variable-speed gear



May 20, 1930. w. JACOBS 1,759,558

VARIABLE SPEED GEAR Filed March 26, 1929 Patented May 20, 1930 UNITED S ATES OFFICE WERNER JACOBS, OF ESSEN, GERMANY, 'ASSIG'NOR TO FRIED. KRUPP AKTIENG-ESELL- SCHAFT, OF ESSEN-ON-THE-RUHR, GERMANY VARIABLE-SPEED GEAR Application filed March 26, 1929, Serial No. 350,059, and in Germany April 4, 1928.

tively connected to the driven shaft through 1 16 each a gear wheel train provided for a certain speed step, independently of the couplin action of the two halves of the main coup ing. This modification is particularly well suited to be employed with a variable speed gear in 20 which resiliently turning. coupling members are arranged between the main coupling and the spur wheeis, for reducingthe frequency of the inherent vibration of the gear. If the two couplings adapted to be operated atwill were arranged before the main coupling, they would be exposed to all variations of the periodically varying turning moment of the driving engine, so that a rapid wear would arise on the engaging faces and a smooth operation would be impossible. This drawback can be obviated according to the invention by arranging the two couplings adapted to beoperated at will behind the main coupling.

In order that the invention can be more 3 easily understood, a preferred embodiment of it is illustrated in longitudinal section in the accompanying drawing, the variable speed gear shown being particularly intended for Diesel engines.

Referring to this drawing, A denotes the driving shaft, C the driven shaft, and B an intermediate shaft. Individual spur wheels, 0 H, J, are mountedon shaft C in combination with free wheel couplings M, i and with positively operated couplings K, 70 0 ,71 and a? L. Wheels F and E are mounted on the intermediate shaft B. in combination with free wheelcouplings G, g f these wheels being in mesh with the wheels 0 and J. The spur wheeld, in mesh with spur wheel H, is

and freely rotatable on shaft B. The other half, A of the main coupling is in permanent rigid connection with the driving shaft and carries friction disks a on both sides of the coupling half N, which disks can be shifted axially, to establish coupling connection. Coaxially with shaft B coupling members I) and P are arranged on both sides of the friction disks a which members, are connected to the coupling half A by springs Q and are capable of slipping relatively to half A against the action of these springs. The coupling member 6* is rigidly connected to' shaft B, and member P is arranged for free rotation on the hollow shaft N Member P further forms at the same time one half of a claw coupling, adapted to operate at will, theappurtenant other coupling half, denoted by 03, being shiftably fixed on the hollow shaft D There is also another positively operated coupling consisting of a half 6 shiftably fixed on shaft B and of the half G of the free Wheelcoupling G, g which half has corresponding coupling claws and is inserted in front of spur wheel E. Spur wheel d can be coupled with the hollow shaft N by a claw coupling having a coupling half n shiftably fixed on shaft N Beside half n there isshiftably mounted on N still another cou- Eling half, a, by which the coupling half can be coupled with half N of the main coupling through the intermediary of the hollow shaft N In describing the operation of the variable speed gear I shall start from a position of the parts as illustrated in the drawing, in which all claw couplings and the main coupling are out of operation,'so that upon the engine being started, first only the parts A A a, P,.b* B revolve.

For running with the wheel train F 0 which corresponds to the first speed step, the coupling halves n G are engaged. Now

when the main coupling N, at A is thrown have reached equal rates of revolution, the cou ling 6 G is thrown in and the coupling 1F and the main coupling N, a A thrown out, so that power transmission now takes place through A, Q, I), B, 6 G, '9 E, F, F 0 The coupling half N the connection of which with the driven parts is interrupted at M, then comes to rest, if not entrained by bearing friction; spur wheel J revolves without load relatively to shaft 0.

To pass to the next higher, speed step cor-- responding to wheel train d H, coupling is, c is thrown in, so that coupling half K now revolves at the same speed as shaft C. Coupling M, d is likewise thrown in, so that spur wheel H is brought to connection with cougling half N (still at rest) through d 11?, N ow upon throwing in again the main coupling N, a A, spur wheel H is, accelerated first, through A, a, N N n ,1d to the speed of the coupling half K that revolves at the rate of shaft C. With further acceleration the free wheel coupling k is automatically. thrown in. The turning moment ofdriving 25 shaft A is now transmitted to shaft 0 through the members A a, N N n, (1 ,11, W K, I0 0 whilst the power transmission that existed in the first speed step is interrupted by free wheel coupling f being'releasedauto .i matically. Shaft C thus has-passed. f'roin,- th'e first to the second speed step jwithout inter ruption of the power transmission, Spur wheel .E "which is connectedgto; shaft B. through claw coupling I), G andifree wheel coupling 9 takes part in the rotation without load, the same being the casewith spur, wheel J loose on shaft 0. As soon as the'cou: pling halves N and A a have reached equal rates of revolution, coupling- 1, disthrown in. Thereu on couplingjbi, G and main conpling N, a, 3 are thrown-out, so that power transmission now takes place through A, Q, P,1Z,D d H, 70 70 053C,

To run at the highest,'third speed step by 45 means of wheel train- E, J, the couplings 0', L and a G are thrown in, Upon throw-' ing in again ,the m'ain coupling N, at A, spur wheel J is first accelerate .u speed of'the coupling half. L' which revolves at the rate of shaft 0, through-the interme diary of the members 'N, N n, G, g, With further acceleration'the free'wheel coi1- pling i automatically starts 'totra'nsmit. The turning momentof the, driving 'shaft A is now transmitted to the driven shaft 0 I through the members A a, N'N 'n, G, 9 E, J, 2?, L, andc whilst the power transmis u sion which was operative in thesecon'd speed step is'interrupted by the free wheel coupling y k automatically being disengaged. ShaftC thus has passed from the second to the third speed step without interruption of the power .transmissioii;- As soon, as the coupling halves N and A e have reached equal rates of revolution; coupling '6, Gris thrown in.

to the E. -nectedto said drivin f member, two alter- The coupling P, d and the main coupling N, a A are then thrown out again, so that the power transmission now takes place through A, Q, 6* B If, Gr, 9 E,-J, '5 L, 0

The passage from a higher speed ste to 'a lower one takes place in a correspon ing manner and needsnot be described in detail. The spur wheel trains corresponding to the three speed steps can also be connected in series, whereby a fourth, very low speed step is obtained, the use of which is required e. g. for the starting of heavily loaded trains or on steep gradients, When .e. g. the locomotive should start at the fourth speed step, the couplings nfld and 5 are thrown in and the other couplings thrown out, if required- Then half N of the main couplin is connection with the driven shaft C t rough N, n 1 Hyh K, 70 7?, J,'E, f, F, 0 "Now upon throwing in t emain cou ling A a, N the drive of shaft 0 takes p ace .over this train with the lowermost gear ratio and with series connection of the wheelrtrains d, H, J, E and F a. When, after the settingoperation has been terminated the' coupling halves A? a and N have reached equal rates of revolution, couplingP, d is-thrown in and coupling 71?, d and the 'main coupling A, a, N thrown outagain, so that'power transmissiOIIQIIOW takes place on the way A A, Q, P,

'Coupling half N then comes to rest, if not entrained by bearing friction, v As tobe seen from the foregoing the two couplings P, d and 6, G adapted to be ope'rated at will and alternately transmitting in theindividual speed steps the power from the driving shaft to the corresponding wheel trains, are .in permanent connection with the driving shaft A through the intermediary of the resiliently turning coupling members? and b, which affords the advantage, asexjfj plained above in detail, that the power trans-Y mission over the engagin faces of the couplings takes place uniform y and theta rapid; wear causing shock eflt'ects is prevented;

Iclaim:@-- a 1. In a variable speed gear a driving member,-"adriven member, a slip clutch, one half ofjsaid slip clutch being permanently connative gear-wheeL trams of different ratios transmission comprisingtwo gear wheels arranged .coa'xiall withsaid slip clutch, a free wheel. coup ngffonfsaid gear-wheel trams, two couplin tobeoperated at will between said gear w as and said clutch half for coupling said gear wheels and said clutch half when said clutch isinoperative,additional couplings to be operated atwillbetweensaid gear wheels andthe other half ofsaid sli clutch, for coupling each of said gear whee. s with said other half, when said slip clutch is inoperative.

In a-variable speed gear as claimed in 1 claim 1,- resilient means inter osed between the-driving halves of said rst-mentioned cou lings and said first-mentioned clutch hal said means permit-ting a relative rotation between said coupling halves and said clutch half.

The foregoing specification signed at Essen, Germany this 11th day of March,

WERNER JACOBS. 

